Investigators say the audio evidence salvaged from the wreckage of the Germanwings plane that crashed in the French Alps appears to suggest that the co-pilot deliberately crashed the plane.

Father of two Martyn Matthews from Wolverhampton died in the crash Credit: Family handout

50-year-old Martyn Matthews from Wolverhampton was amongst the one hundred and fifty people who died in the crash on Tuesday.

Prosecutors believe the German co-pilot, Andreas Lubitz, caused the crash deliberately after the captain left the cockpit, and then wasn't let back in. Prosecutors added there were no grounds to consider it was a terrorist incident.

Marseille prosecutor Brice Robin said the German co-pilot Andreas Lubitz appeared to deliberately drive the plane into the ground, but said there were no grounds to consider it was a terrorist incident.

There is no reason to suspect a terrorist attack.

– Brice Robin

Asked whether he believed the crash that killed 150 people
was the result of suicide, he said:

People who commit suicide usually do so alone....I don't call it a suicide.

– Brice Robin

He also said it did not appear that the passengers realised what was happening until the last moment.

One of the pilots on the German Airbus plane that crashed in the French Alps, killing everyone onboard, left the cockpit and was unable to return before the plane went down, the New York Times reported, citing evidence
from a cockpit voice recorder.

"The guy outside is knocking lightly on the door and there is no answer," an unnamed investigator told the Times. "And then he hits the door stronger and no answer. There is never an answer."

"You can hear he is trying to smash the door down," the investigator added.